Dyno Test #2
Written by HighFive
Dyno Test #2
Today was the not-so-long awaited day to return R² to the DynoStar at Koweta Custom Cycles sporting the shiny new FMF Powerbomb Header & Q4 combo. We spent 1½ hours on the Dynostar, made 7 runs, and learned a lot!
Before the whining begins, I'll clarify that the atmospheric conditions were fortunately similar to my first test.
Test 1 on 12/08/08: 58.9 degrees & 28.88 in. HG
Test 2 on 12/19/08: 50.0 degrees & 29.39 in. HG
So, not too much to complain about there.
For a refresher, let's look again at the result of Test 1; 22.1 Hp & 14 ft-lbs Torque. This was with the stock header & muffler, with SA removed and Graves Insert installed. FMF-PP at 3-3-3-8-8-8.
So, first order of business today was to run a new baseline at the same settings with only the pipe header & muffler change. This graph shows the result with the FMF Powerbomb & Q4 installation:
23.7 Hp & 16 ft-lbs Torque. Now, hold your hat and don't jump to conclusions just yet. That was a 1.6 Hp & a 2.0 ft-lb Torque gain. So I had a 7% increase in Hp and a 14% increase in Torque at this point. Interesting. Also, you can immediately see that we were able to fix the O2 sniffer problem from Test 1. The Q4 muffler was much more cooperative in allowing the sniffer to be inserted deep into the Can for a valid reading. You can now trust the Air/Fuel Mixture readings in the lower half of the rpm range. So, now I can get down to some serious business.
Next up, is the result of all our tweaking to dial-in the FMF-PP to optimal performance:
24.5 Hp & 16 ft-lbs Torque. Squeezed almost 1 more pony out of her at gain of 0.8 Hp....no change in Torque. We settled on 3-5-0.5-8-4-4. This is very close to same as Steveakus' best Dyno #'s over on TT. So, solid validation of his suggested settings.
There are three challenges I found tuning the engine, as you can see thru the Dyno runs: 1) too rich off bottom 2) too lean thru acceleration 3) too rich on top (WOT). I can't do anything to solve the problem off the very bottom, unless I get a Power Commander Unit which could be dialed in at a Dyno Test. I'm not sure I'd settle (personally) for someone else's curve. Each bike runs a little different and has its on quirks & preferences. Based upon these results, I don’t believe a Power Commander would yield any higher Hp than an FMF unit, but might offer the very low end a bit stronger pull off bottom by leaning it out a bit. But that's unknown (by me) at this time.
Anyway, I was able to richen the acceleration level (around 4,500 - 5,500 RPM) to an acceptable level between 13 - 14%. Fixing the WOT was easy by running the setting back down to the minimum possible. It did not need to be any leaner. We are not in any danger of running our R²'s too lean at WOT...all day long....under any normal circumstance. And, I'm about to show you why...
Strap on your seat belt for this final plot. I opened the airbox door and told the Tech to make a final run on the Dyno drum. Here's what happened:
26.8 Hp & 17 ft-lbs Torque! Ho-chi-momma!!! A 2.3 Hp gain & 1 more ft-lb of Torque! Note: this is with a K&N air filter. That brings the total gains to nearly 5 Hp (4.8) and 3 ft-lbs of Torque. There is the "Delta" that everyone has been waiting to see. And, with all this extra air she did not run much leaner at WOT. In fact, the Air/Fuel looks pretty stable....all things considered.
Poor R² is suffocating to death! I did this when I had the stock pipe on, and it really didn't make much difference. So, the bottom line is a pipe change IS beneficial IF you incorporate these other mods. More air coming in is pretty useless if it can't get out thru a plugged up pipe! Yama got her corked to an art form.
So, all the guys that have busted out the tops of their airboxes, whether intentionally or not, really DO have an advantage IF they've done these other mods in conjunction.
I've been looking over my airbox and thinking about different ways to enlarge the intake and allow more air to enter the collection chamber. I’ll post another article on my airbox mods in a separate post.
That's all folks! The numbers don't lie. Oh, one more thing. I got the fine opportunity to see hard proof of the difference between a DynoStar and the more common DynoJet machines. I saw actual plots of the same bike (a Harley) on both types of machines....made on the same day. The DynoJet results were 10% higher than the DynoStar. I think that is why the DynoStar is claimed to produce "raw numbers".....which I think means "real numbers" if I understand things correctly. Sounds like DynoJets can average between 5 -10% higher readings. Difference in cost of machine components, I guess.
Anyway, if you add 10% to my 26.8 Hp measurement, you get 29.5 Hp. Sound familiar? Maybe I don't have a dud after all.
Couple more things...because someone has asked me via the forums. Maybe others want to know too.
1) Does the FMF Spark Arrestor make a difference?
The spark arrestor on the Q4 made no performance change whether in or out. So, its good to know you can leave it in. Your not giving up any power. Just remember to remove it and clean the screen once in a while.
2) Where did I purchase my FMF pipe? What did I pay?
I found a guy on ebay who saved me $100 on the combo. Didn't know him, never bought from him before. He was very responsive to my inquiries and questions. Gave me outstanding service! Did exactly what he said he could & when he would. I give him 5 stars (service & price) - 1 star (for no website yet) = 4 stars. His name was "Devon". Contact: This e-mail address is being protected from spambots. You need JavaScript enabled to view it Phone: 805-426-5700. I paid $164.95 for the Powerbomb Header (FMF#044269) and $294.95 for the Q4 muffler (FMF#044271) and he offered free shipping via ground. That was $459.90 for the combo.
Don't know how much of the difference is affected by the Powerbomb header. Maybe not much accept helps lower sound output (if advertisement is accurate). It does have a larger pipe ID than the stock header, so it may be important component. I donno....for certain. But it does look "mean & cool". They are real nice mated parts. Doesn't even require a compression clamp at the mid-section where they mate. Just goop the joint real good with Hi-temp copper gasket manifold sealer (like Permatex). I have ZERO exhaust leakage in the joint. We checked it thoroughly with a sensitive "sniffer" during the Dyno Test 2. Nada...nothing. Hope it stays that way. There are no slits in the muffler opening. Its a solid pipe. Compressing it (if you can) would only cause deformation in the pipe which could lead to an exhaust leak at the mid section joint (IMO). But, what do I know...
HF